A quantitative meta-analysis of vitamin C in the pathophysiology of Alzheimer’s disease

Abstract

PurposeAlzheimer’s disease (AD) is a multifaceted neurodegenerative disorder with many complex pathways feeding into its pathogenesis and progression. Vitamin C, an essential dietary antioxidant, is vital for proper neurological development and maintenance. This meta-analysis and systematic review attempted to define the relationship between vitamin C plasma levels and AD while highlighting the importance and involvement of vitamin C in the pathogenesis of AD.Materials and methodsPRISMA guidelines were used to obtain studies quantifying the plasma levels of vitamin C in AD and control subjects. The literature was searched in the online databases PubMed, Google Scholar, and Web of Science. A total of 12 studies were included (n = 1,100) and analyzed using Comprehensive Meta-Analysis 3.0.ResultsThe results show that there is a significant decrease in the plasma vitamin C levels of AD patients as compared to healthy controls (pooled SMD with random-effect model: −1.164, with 95%CI: −1.720 to −0.608, Z = −4.102, p = 0.00) with significant heterogeneity (I2 = 93.218). The sensitivity analysis showed directionally similar results. Egger’s regression test (p = 0.11) and visual inspection of the funnel plot showed no publication bias.ConclusionBased on these studies, it can be deduced that the deficiency of vitamin C is involved in disease progression and supplementation is a plausible preventive and treatment strategy. However, clinical studies are warranted to elucidate its exact mechanistic role in AD pathophysiology and prevention.

Ablation of placental REST deregulates fetal brain metabolism and impacts gene expression of the offspring brain at the postnatal and adult stages

“…In fact, the brain needs more ascorbate than any other organ 81 . Links of vitC deficiency with brain diseases such as Parkinson's disease 82 and Alzheimer's disease (AD) are known 83–86 . Therefore, our study suggests that understanding the role of placental REST in the maintenance of brain vitC in the postnatal stages is important to investigate the developmental origin of health and disease (DOHaD) of the adult brain 79 …”

“…81 Links of vitC deficiency with brain diseases such as Parkinson's disease 82 and Alzheimer's disease (AD) are known. [83][84][85][86] Therefore, our study suggests that understanding the role of placental REST in the maintenance of brain vitC in the postnatal stages is important to investigate the developmental origin of health and disease (DOHaD) of the adult brain. 79 Our findings further show that DNA methylation is impacted in the adult brain due to the loss of placental REST, but in a sex-biased manner.…”

Serum vitamin C levels and their correlation with chronic kidney disease in adults: a nationwide study

“…In contrast, serum vitamin C levels offer a more robust assessment of tissue vitamin C, providing valuable insights into its functions in disease prevention [ 28 ]. Numerous studies have underscored the close relationship between serum vitamin C concentration and the risk of various chronic diseases, including heart failure [ 29 ], cancer [ 30 , 31 ], cognitive dysfunction [ 32 ], and Alzheimer’s disease [ 33 ]. A prior study in Japan observed a positive linear correlation between serum vitamin C concentration and eGFR [ 34 ].…”

A bibliometric review on vitamins and Alzheimer’s disease between 1996 and 2023

“…According to the analysis of the co-citation count among the 10 references, most were human experiments, and four were randomized controlled trial (RCTs). The number of citations can be regarded as a relatively reasonable indicator to evaluate the quality of publications, which indicates that vitamins D, E, and B are the focus of current research, but recent research shows that vitamin C supplementation is a feasible strategy for prevention and treatment of AD (Hamid et al, 2022), Vitamin C treatment restored Aβ induced abnormal metabolites, and the role of antioxidants in the repair of AD metabolic disorder provide a new metabonomic observation and explanation (Zhang et al, 2022). Thus, VK2 may also play an important role in the prevention and treatment of AD (Popescu and German, 2021).…”